Topiramate as an adjuvant treatment with atypical antipsychotics in schizophrenic patients experiencing weight gain

Schizophrenic patients commonly suffer weight gain, which is often associated with widely prescribed antipsychotic medicines. It is distressing to most patients who experience it and may affect their response to treatment of schizophrenia. Weight gain is also associated with treatment noncompliance and several medical conditions. This study explored the efficacy and tolerability of topiramate as an adjuvant treatment of patients with schizophrenia who were carrying excess weight. In this 12-week, randomized, placebo-controlled prospective study, 66 hospitalized patients with schizophrenia who were carrying excess weight were given topiramate at doses of 100 mg/day or 200 mg/day, or a placebo. The primary measures made were body weight, body mass index, waist measurement, hip measurement, and waist-to-hip ratio. Safety measures included physical examinations and the monitoring of adverse effects, clinical laboratory data, and vital signs. The Clinical Global Impression-Severity of Illness scale (CGI-S) and the Brief Psychiatric Rating Scale (BPRS) were used to quantify changes in schizophrenic symptoms and signs. In the 200-mg/day topiramate group, body weight, body mass index, waist measurement, and hip measurement decreased significantly compared with the 100-mg/day topiramate and placebo groups over 12 weeks. However, the waist-to-hip ratio did not change in any group. Scores on the CGI-S and BPRS decreased significantly over the 12-week period in both topiramate groups, but the decrease was not clinically meaningful. These results suggest that a higher dose of topiramate is efficacious as an adjuvant treatment of patients with schizophrenia experiencing excess weight gain. Further clinical research is required to establish guidelines for the use of topiramate as an antiobesity agent in schizophrenic patients.